Storytelling does have its ethics, but they’ve never been much concerned with full and transparent disclosure. If a writer wants to fool you into believing that Character A is sweet and benign, only revealing in the final chapter that he’s the fetishistic serial killer everyone’s been looking for, readers are unlikely to demand their money back on the grounds that they’ve been knowingly misled. Being misled, skilfully and teasingly, is what they paid for.

What about television documentaries though? Are they entitled, as part of a narrative striptease, to keep an audience in ignorance of hard facts simply because the truth is too dull to keep anyone watching? I’m inclined to think not, which brings us to Alien Investigation, a Channel 4 documentary (and I use the term very loosely) that displayed all the fastidious ethical nicety of a time-share salesman.

To be fair, you only have yourself to blame if you were gulled for a moment. Everything about Alien Investigation, from the way the script was almost entirely composed of ominous- sounding questions to the wildly self-deluding experts who appeared in the early sections, should have told you that 90 per cent of the programme was going to be the equivalent of a freak show’s painted promises, while 10 per cent would be reserved for the disappointingly squalid reality. So the carney advert gave you the Montauk Monster, a mysterious washed-up corpse with “no match to any known species”. Could it be the product of secretive breeding experiments at the government institute on nearby Plum Island? Or the tragic remnants of an alien visitor? Well, no actually, it was a decomposing racoon.

The other “mysteries” were picked apart with similar ease, their mystery, at least as far as the film-makers were concerned, consisting in little more than effortful equivocations designed to delay the moment at which we realised we’d been sold a pup. To pad the thing out even further, fanciful animations and computer graphics had been commissioned to illustrate explanations that everyone concerned – apart perhaps from the wildly gullible promoters of these finds – knew to be false. The Alien Mummy of Metepec, a strange homunculus allegedly caught on a Mexican ranch, turned out to be a marmoset. But that revelation was illustrated not by a reconstruction of the confessed hoax involved, but with a rerun of a Gollum-like extra-terrestrial swishing its tail.

The expert we really needed, in truth, was a psychologist, to dissect the odd compound of longing and self-deception that guarantees a steady supply of people willing to ignore the blindingly obvious in favour of the highly fanciful. Like the man who carefully interpreted an Inca mask, which, he claimed, depicted a helmeted alien, drawing down power from two “energy sources” as he sat in front of a flying saucer “control panel”. How ingenious of our other worldly visitors to make the control panel so mouthlike, the alien himself so nasal, and then place the circular “energy sources” exactly where a pair of human eyes would go. I don’t know about alien forms of intelligence out there in space, but there’s no shortage of it down here on earth.

Solar Mamas was a touching documentary about an Indian enterprise that teaches women from poor rural communities to become solar-power engineers. The idea is that they take the technology back home and teach it to more people, spreading light in the darkness. That it is also interested in other forms of enlightenment seems clear from the fact that only women are trained, a fact that caused problems for Rafea, a Jordanian Bedouin selected for the project. The tension here was genuine, not ersatz. Could she overcome her husband’s prejudice and wounded pride to complete the course and fulfil her own ambitions? I’m glad to say she could. If you wanted to get the taste of Alien Investigation out of your mouth, it was close to perfect.